Multicolor facsimile recorder



March 15, 1960 G. MANDEL MULTICOLOR FACSIMILE RECORDER Filed Oct. 20, 1958 26 28 MARKING SIGNAL ....Z

MARKING SIGNAL SOURCE SOURCE M. 5. SOURCE 70 M. 5. SOURCE FIG. 8.

SIGN AL 4 SOURCE A. C. MARKING INVENTYOR GERALD MANDEL UQ ATTORNEY United States Patent MULTICOLOR FACSIMILE nsconnnn Gerald Mandel, Elmhurst, N.Y., assignor to Faximiie, Inc., New York, N.Y., a corporation of Delaware Application October 20, 1958, Serial No. 768,167

20 Claims. (Cl. 346-74) This invention relates to the art of facsimile recorders and particularly concerns an apparatus for producing multicolored graphic copy electrically.

One of the most successful electrical recording systems involves the passage of electric current from an electrically positive electrode through an electrolytic recording paper to a negative electrode. In the recording process, the positive electrode or anode erodes or dissolves while reacting with a marking compound in the paper to form a mark. The negative electrode or cathode is not eroded during marking. Conventional recorders of this type, such as described in US. Patent No. 2,575,- 959 issued on November 20, 1951 to John V. L. Hogan,

, normally employ a straight metal bar as the anode and a rotatable metal helix as the cathode. This recording apparatus produces highly satisfactory graphic copy in which the recorded marks are black or some shade of grey, particularly when there is employed electrolytic recording paper of the type described in [1.3. Patent No. 2,339,267 issued on January 18, 1944 to John V. L. Hogan et al. Attempts have been made in the past to employ the bar and helix type of facsimile recorder for producing graphic copy having colors other than black. This has been successfully accomplished by employing suitable marking compounds. Thus by using chromotropic acid and an iron bearing anode as described in my copending patent application U.S. Serial No. 753,075, filed August 4, 1958, I have produced green marks electrolytically. Other metal anodes such as titanium produced brick red marks With chromotrop-ic acid. The same metals with 8-hydroxyquinoline produce green and yellow marks respectively. According to the present invention, I have found it possible by employing a plurality of anodes which are disposed in close proximity to each other so as to be either immediately adjacent to each other or else closely spaced from each other and which are made of different metals to produce marks of different hues on electrolytic recording paper in a facsimile recorder. I have further found that it is possible to vary the color tones of the hues by applying alternating current marking signals at various frequencies and amplitudes. For example, the apparatus will record brown, red or green hues whose color tones vary from dark to light brown, red or green.

.The apparatus further produces the rather unexpected result of recording marks of varying density which are mixtures of individual primary or basic colors which the apparatus is capable of recording. Thus it is possible to reproduce electrically good facsimile copies of colored photographs, prints, paintings, drawings, etc.

It is therefore a principal object of the invention to provide a facsimile recorder capable of recording colored marks having different hues, different color tones, and different intensities of color.

It is a further object to provide an apparatus employing electrolytic recording paper for recording colored marks in which means is provided for varying the color,

color tone and intensity of color of the marks according to the character of the applied marking signals.

It is a still further object to provide an electrolytic recording apparatus employing two or more closely disposed electrodes made off different metals capable of reacting with a marking compound in an electrolytic recording paper to produce marks of various colors.

It is a still further object to provide anelectrolytic recording apparatus of the character described in which alternating current marking signals of variable frequency and/or amplitude are employed to form colored marks having various color tones and color intensities.

Other and further objects and advantages of the invention will become apparent from the following detailed description taken together with the drawing, wherein:

Fig. 1 is an elevational view partially diagrammatic of a recorder embodying the invention.

Fig. 2 is an end view also partially diagrammatic of the recorder of Fig. 1.

Fig. 3 is a perspective view of one form of electrode assembly usable in the recorder.

Fig. 4 is a sectional view on an enlarged scale taken on lines 4-4 of Fig. 3.

Fig. 5 is a sectional view similar to Fig. 4 of the electrode assembly shown in Figs. 1 and 2.

Figs. 6 and 8 are end views partially diagrammatic and similar to Fig. 2 of other recorders embodying the invention.

Figs. 7 and 9 are perspective views of electrodes used in the recorders of Figs. 6 and 8 respectively.

Referring to Figs. 1 and 2 there is shown a graphic recorder including a drum 10 carrying a metal single-turn helical electrode 12. A laminated electrode assembly 14 is disposed to intersect the helical electrode. This assembly includes a slotted bar 16 made of electrical insulation material in which is secured a pair of thin metal blades 18 and 2h. The blades are straight and parallel to each other. As best shown in Fig. 5 the blades extend from one side of the bar 16 and are spaced a short distance D which should not exceed .02 of an inch and preferably not exceeding the thickness of either blade. The blades are made of difierent metals. The bottom edge E of each blade is disposed to contact one side of a movable porous web of electrolytic recording paper 22. The other side of the web is contacted by the rotatable helical electrode. The blades 18-and 20 thus provide two electrodes which are insulated from each other in the holder 16. Each blade has a lug 24 which extends out of the holder for connection of an electrical conductor 26 or 28 thereto. A flexible mounting member 30 may be secured to the bar 16 for mounting the electrode assembly 14 resiliently on a support 32 by screws 31. Member 3t) insures that the physical contact of the edges E of blades .18 and 20 with the recording paper is maintained. The drum 10 is rotated by a motor 34.

Marking signals are applied to the electrodes 18 and 20 via wires 26, 28 from suitable electrical sources '42 and 44 which provide marking signals which may vary in amplitude depending upon the variations in color tone and intensity of color desired in the recorded marks. The return circuits to the sources of marking signal are connected in common to the helical electrode via a wire 29, conductor 36 and contact member 38 which maintains a continuous electrical circuit with electrode 12 via shaft 40.

In operation of the recorder, two dififerently colored marks will be formed in the paper 22 at the points of intersection of the individual blades 18, 20 and the electrode 12. Because of the closeness of spacing of the linear electrodes and the porosity of the paper the two marks will spread and merge into each other so that only a single colored mark will be formed which is' a chromatic blend of both colored marks and which has a size somewhat larger than the combined areas of the two marks initially formed. The closeness of spacing of the two electrodes is essential for the merging of the discrete marks. 'A spacing in excess of .02 01" an inch results in separate colored marks instead of a merged, blended mark.

Since each linear blade extends transversely across the paper substantially perpendicular to the path of movement thereof, there will actually be formed two closely spaced differently colored lines during each revolution of the helical electrode, but these lines will merge into a single line of blended color due to the porosity of the paper as above mentioned as well as the essential close spacing.

if the amplitude of the marking signal applied to any one electrode is varied while the amplitude of the other is held constant, there will be a change in color tone. if the amplitudes of t.e marking signals to both electrodes are varied, then the intensity of the color of the mark will vary while the color tone remains the same. Thus a medium green colored mark may be varied from dim to brilliant while remaining medium green.

In one application of the invention D.C. marking currents were applied from separate sources 42 and 44 to linear electrodes 1?; and 21) in which one electrode was made of steel (containing iron) and the other electrode was made of titanium. The recording paper contained chromotropic acid as the marking compound. Individually, the respective electrode marked green and brick red. The blended marks varied depending on the relative amplitudes of the two marking signals. Thus by increasing the amplitude of the signals applied to the steel electrode the composite mark Was made predorninately green. By increasing the amplitude of the signals applied to the titanum electrode, the composite mark was made predominately red-orange.

it is possible to employ more than two linear electrodes of different metals in the recorder. Thus as shown in Figs. 3 and 4, the insulated holder bar 16a carries three blades 18, 19 and 2t closely spaced a distance D from each other in a laminated assembly 14a. Three separate sources of marking signals may be connected to the respective marking blades via contact elements 2%.

Use of three linear electrodes, each formed of different metal and each provided. with marking signals from a different variable amplitude marking source, provides recording with a maximum range of colors, color tones. and color tone intensities.

Each of the three marking signal sources may be one of three photocells employing a separate optical filter for each photocell to scan vari-colored copy as described in U.S. Patent 1,854,315. Each photocell will generate electrical signals corresponding to a certain color at each point scanned by the photocell. The several scanning signals can be transmitted to the several linear electrodes of the three-electrode assembly I ia in a recorder as described above to reproduce faithfully the scanned colored copy. Preferably, each optical filter would select colors corresponding to a different one of the three primary colors red, yellow and blue. For such a system, the recording paper 22 may contain po tassium ferrocyanide as a marking compound, and the linear electrodes 18, 19 and 2t) might be copper, silver and stainless steel (containing iron). When used separately, these electrodes would produce generally red, yellow and blue marks respectively with the marking compound. The respective colored marks would be blended as desired by varying the amplitude or frequency of the applied marking signals. Other color combinations may be obtained by using other metals in the electrodes and other marking compounds in the recording paper. r I In Fig. 6 is shown another form of the invention in which the linear electrodes 56 and 58 are blades having a generally right-angle cross section. The electrodes are independently mounted on supports s0 and 61. Each electrode has a straight marking edge E on one flat side 59 as best shown in Fig. 7. The electrode includes fingers 62, d3, 64 integrally joined to the upper nonmarking side 55. One of the fingers has a tab or lug 65 to which can be connected the marking signal Wire 26 or 253. Springs an, 67 may be connected between openings 69 in the fingers and the insulated support 68 to maintain contact between the marking edges E of the electrodes and the recording paper 22. It will be noted that each of the electrodes 56 and 58 are so mounted that their marking edges E are closely spaced and parallel. The spacing should not exceed .02 of an inch and preferably should not exceed the thickness of the blades at the marking edges. This spacing requirement is the same as that of the electrode assemblies 14, 14a. The variable amplitude marking signal sources 42 and 44 would be electrically connected to electrodes 56, 58 via wires 26 and 2%, and to the rotatable electrode 12 via 33 and 35. This recorder produces blended colored marks in the same manner as the recorder of Figs. 1 and 2.

It is possible to obtain colored marks according to the inventor by employing AC. or DC. marking signals. The invention makes it possible to employ frequency modulated signals for marking. Thus the signals may vary in frequency while the amplitude remains substantially constant. Signals which vary in frequency will produce a variation in color tone in a manner similar to a variation in amplitude.

When a variable frequency signal source is employed it is possible to use the recorder arrangement of Figs. 8 and 9 in which a laminated blade assembly 14b has juxtaposed linear blade electrodes 18, 19 and 29 formed of different metals. This electrode assembly includes a slotted metal bar 17 in which is mounted the three blades i8, 19 and 2t! juxtaposed to each other with each blade in contact with the blade adjacent to it, as shown. A single A.C. marking signal source 73 is connected electrically to all blades via Wire 27', holder 3d and bar 17. The rotatable electrode 12 is connected to the marking signal source via Wire 36, shaft 40, contact and wire 2?.

In operation of the recorder of Fig. 8 each blade 18, 19, 2% will mark in its own color but the resulting colored mark will be a composite or blend of the three marks. This eliect will be substantially the same as ob- .ained with the recorders of Figs. 1 and 6 except that finer marking lines may be obtained with the juxtaposed, laminated blade structure of Fig. 9 than with the spaced blade structures of Figs. 4 and 5.

It will be noted that in the recording apparatus of Fig. 8 the applied marking signals are preferably alternating currents. This is a departure from the conventional practice in which direct current is normally employed in electrolytic recording. Heretoiore it has been considered undesirable to mark electrolytic recording paper with alternating current because it was thought that duriug alternate half cycles of the current how, the rotating helical electrode would become the anode and would be eroded. it has been discovered in practising the present invention, that the erosion of the helical electrode can be prevented by making this electrode of a noble metal allow (preferably platinum) which erodes to an insignificant extent during marking.

The use of alternating current in marking is important to the present invention since it is the variable frequency of the applied current which determines the color tone of the mark. The color of the mark is basically determined by the metallic composition of the electrodes and by the particular formulation of the marking compound in the recording paper.

If desired, vthe same A.C. marking signal source can be applied to both spaced electrodes 18, 20 or 56, 58

instead of the independent signal sources 42, 44. This arrangement would be then equivalent to the arrangement of Fig. 8 in which the same marking signals are applied to all the electrodes simultaneously. The variations in color of the blended mark would then be obtained preferably by varying the frequency of the applied A.C. marking signals. Each change in frequency and each signal frequency will cause each metal electrode to mark with a different color tone so that the resultant color of the blended marks would be readily controllable. Of course the amplitude of the applied signals could be varied as well as the applied frequencies so that the blended colored marks are selectively controllable and variable by both amplitude modulated and frequency modulated signals simultaneously. It will be noted that the present invention makes it possible to employ a source of frequency modulated signals to actuate an electrolytic recorder which is most unusual in the art and in addition makes it possible to produce colored marks whose color is variable by varying the frequency of the signals.

When reference is made in the claims to the electrodes or portions of the electrodes being juxtaposed or disposed in close proximity to each other, such reference is to be construed as including constructions in which the electrodes are closely spaced from each other and also constructions in which the electrodes are immediately adjacent to one another or in contact with one another.

The foregoing embodiments have been described and illustrated by way of example, and it will now be apparent to those skilled in the art that various modificaitons and changes may be made without departing from the spirit and scope of the invention as defined by the appended claims.

What is claimed is:

1. A color facsimile recorder, comprising a first electrode, a recording medium containing an electrically markable compound, said electrode being disposed to contact one side of said recording medium, and an electrode assembly including a plurality of substantially parallel linear electrodes each having a fine marking edge in contact with the other side of the recording medium and intersecting the first electrode, each of said linear electrodes being formed of a different metal for reacting with said compound to produce a mark of different color, said recording medium being porous so that the colored marks produced by said linear electrodes merge to form composite colored marks in the recording medium.

2. A color facsimile recorder, comprising a first electrode, a recording medium containing an electrically markable compound, said electrode being disposed to contact one side of said recording medium, and an electrode assembly including a plurality of substantially parallel linear electrodes each having a fine marking edge in contact with the other side of the recording medium" and intersecting the first electrode, each of said linear electrodes being formed of a different metal for reacting with said compound to produce in said medium a mark of different color, said recording medium being porous and said linear electrodes being disposed in close proximity to each other so that the colored marks produced thereby merge to form composite colored marks in the recording medium.

3. A color facsimile recorder, comprising a rotatable electrode, an electrically conductive recording medium containing an electrically markable compound, said electrode being disposed to contact one side of said recording medium, an electrode assembly including a plurality of substantially parallel linear electrodes each having a fine marking edge in contact with the other side of the recording medium to maintain an electrical circuit through the recordingmedium to said rotatable electrode, each of said linear electrodes being formed of a different metal for reacting with said compound to produce a mark of a different color, said recording medium being porous so that colored marks produced by said linear electrodes merge to form composite colored marks in therecording medium. I

4. A color facsimile recorder, comprising a rotatable electrode, an electrically conductive recording medium containing an electrically markable compound, said electrode being disposed to contact one side of said recording medium, an electrode assembly including a plurality of substantially parallel linear electrodes each having a fine marking edge in contact with the other side of the recording medium and maintaining a direct electrical circuit through the recording medium to said rotatable electrode, each of said linear electrodes being formed of a different metal for reacting with said compound to produce a mark of a different color, said recording medium being porous so that colored marks produced by said linear electrodes merge to form composite colored marks in the recording medium, said linear electrodes being juxtaposed to each other at their marking edges.

5. Multicolor facsimile apparatus comprising a rotatable electrode, an electrically conductive recording medium containing an electrically markable compound, said electrode being disposed to contact one side of said recording medium, an electrode assembly including a plurality of substantially parallel linear electrodes eachhaving a line marking edge in contact with the other'side of the recording medium and maintaining a direct electrical circuit through the recording medium to said rotatable electrode, each of said linear electrodes being formed of a different metal for reacting with said compound to produce a mark of a different color, saidrecording medium being porous so that colored marks produced by said linear electrodes merge to form composite colored marks in the recording medium, said linear electrodes being juxtaposed to each other at their marking edges, and a source of marking signals electrically coupled to the rotatableelectrode and electrode assembly and providing alternating currents of variable frequency to said circuit.

6. Multicolor facsimile apparatus comprisinga rotatable electrode, an electrically conductive recording medium containing an electrically markable compound, said electrode being disposed to contact one side of said recording medium, an electrode assembly including a plurality of substantially parallel linear electrodes each having a fine marking edge in contact with the other side of the recording medium and maintaining a direct electrical circuit through the recording medium to said rotatable electrode, each of said linear electrodes being formed of a different metal for reacting with said compound to produce a mark of a different color, said recording medium being porous so that colored marks produced by said linear electrodes merge to form composite colored marks in the recording medium, said linear electrodes being juxtaposed to each other at their marking edges, and a source of marking signals electrically coupled to the rotatable electrode and electrode assembly and providing alternating currents of variable frequency to said circuit, said rotatable electrode being formed of a metal chemically inert with respect to said compound.

7. Multicolor facsimile apparatus comprising a first electrode, an electricaliy conductive recording medium containing an electrically markable compound, said electrode being disposed to contact-one side of said recording medium, and an electrode assembly including a plurality of parallel linear electrodes each having a fine marking edge in contact with the other side of the recording medium and intersecting the first electrode, each of said linear electrodes being formed of a different metal for reacting with saidcompound to producefa mark of different color, said recording medium being porous so that the colored marks produced by said linear electrodes merge to form composite colored marks in the recording medium, said linear electrodes being juxtaposed to each other at their marking edges, and a source of alternating wens coupled to the first electrode and said electrode assembly.

8. A color facsimile recorder, comprising a first electrode, a recording medium containing an electrically markable compound, said electrode being disposed to contact one side of said recording medium, and an electrode assembly including a plurality of parallel linear electrodes each having a fine marking edge in contact with the other side of the recording medium and intersecting the first electrode, each of said linear electrodes being formed of a different metal for reacting with said compound to produce in said medium a mark of ditferent color, said recording medium being porous and said linear electrodes being closely spaced so that the colored marks produced thereby merge to form composite colored marks in the recording medium, said linear electrodes being insulated from each other in said assembly.

9. Multicolor facsimile apparatus comprising a first electrode, a recording medium containing an electrically markable compound, said electrode being disposed to contact one side of said recording medium, and an electrode assembly including a plurality of substantially parallel linear electrodes each having a fine marking edge in contact with the other side of the recording medium and intersecting the first electrode, each of said linear electrodes being formed of a different metal for reacting with said compound to produce in said medium a mark of different color, said recording medium being porous and said linear electrodes being closely spaced so that the colored marks produced thereby merge to form composite colored marks in the recording medium, said linear electrodes being insulated from each other in said assembly, and a plurality of separate signal sources electrically coupled between the respective linear electrodes and said first electrode.

10. A color facsimile recorder, comprising a first electrode, a recording medium containing an electrically markable compound, said electrode being disposed to contact one side of said recording medium, and an electrode assembly including a plurality of substantially parallel linear electrodes each having a fine marking edge in contact with the other side of the recording medium and intersecting the first electrode, each of said linear electrodes being formed of a different metal for reacting with said compound to produce in said medium a mark of different color, said recording medium being porous and said linear electrodes being closely spaced so that the colored marks produced thereby merge to form composite colored marks in the recording medium, the spacing of the marking edges of said linear electrodes being not greater than 0.02 of an inch.

11. In a color facsimile recorder, an electrode assembly comprising support means, and a plurality of metal electrodes mounted by said means and having respective marking edges disposed in close proximity to each other, each of the electrodes being formed of a different metallic composition.

12. In a color facsimile recorder, an electrode assembly comprising support means, and a plurality of metal linear electrodes supported by said means with respective linear marking edges substantially parallel to each other and in close proximity to each other, each of the electrodes being formed of a different metallic composition.

13. In a color facsimile recorder, an electrode assembly comprising a holder, and a plurality of metal linear electrodes having closely spaced marking edges substantially parallel to each other, each of the electrodes being formed of a different metallic composition, said electrodes being closely spaced and insulated from each other in the holder.

14. In a color facsimile recorder, an electrode assembly comprising a holder, and a plurality of metal linear electrodes having marking edges substantially parallel to each other, each of the electrodes being formed of a diiferent metallic composition, said electrodes being closely spaced and insulated from each other in the :holder, said marking edges being juxtaposed and closely spaced from each other.

15. In a facsimile recorder for marking a recording medium containing an electrically markable compound, the combination comprising a first electrode, said electrode being disposed to contact one side of said recording medium, and an electrode assembly including a plurality of substantially parallel linear electrodes each having a fine marking edge for contact with the other side of the recording medium and intersecting the first electrode, each of said linear electrodes being formed of a 7 different metal for reacting with said compound to produce a mark of d fferent color.

16. In a facsimile recorder for marking a recording medium containing an electrically markable compound, the combination comprising a first electrode, said electrode being disposed to contact one side of said recording medium, and an electrode assembly including a plurality of substantially parallel linear electrodes each having a fine marking edge for contact with the other side of the recording medium and intersecting the first electrode, each of said linear electrodes being formed of a different metal for reacting with said compound to produce a mark of different color, said linear electrodes being closely spaced so that colored marks produced thereby merge to form composite colored marks in the recording medium.

17. A color facsimile recorder for marking a recording medium containing an electrically markable compound, the combination comprising a rotatable electrode, said electrode being disposed to contact one side of said recording medium, and an eiectrode assembly including a plurality of substantially parallel linear electrodes each having a fine marking edge for contact with the other side of the recording medium to maintain a direct electrical circuit through the recording medium to said rotatable electrode, each of said linear electrodes being formed of a ditierent metal for reacting with said compound to produce a mark of a difierent color.

18. A color facsimile recorder for marking a recording medium containing an electrically markable compound, the combination comprising a rotatable electrode, said electrode being disposed to contact one side of said recording medium, and an electrode assembly including a plurality of substantially parallel linear electrodes each having a fine marking edge for contact with the other side of the recording medium to maintain a direct electrical circuit through the recording medium to said rotatable electrode, each of said linear electrodes being formed of a different metal for reacting with said compound to produce a mark of a different color, said linear electrodes being juxtaposed to each other at their mar.- ing edges.

19. Multicolor facsimile apparatus for marking an electrically conductive recording medium containing an electrically markable compound, the combination comprising a rotatable electrode, said electrode being disposed to contact one side of said recording medium, and an electrode assembly including a plurality of substantially parallel linear electrodes each having a fine marking edge for contact with the other side of the recording medium to maintain a direct electrical circuit through the recording medium to said rotatable electrode, each of said linear electrodes being formed of a difierent metal for reacting with said compound to produce a mark of a difierent color, said linear electrodes being disposed in close proximity to each other at their marking edges, and a source of marking signals electrically coupled to the rotatable electrode and electrode assembly and providing alternating currents of variable frequency to said circuit.

20. In a facsimile recorder for marking a recording medium containing an electrically markable compound, the combination comprising a first electrode, said electrode being disposed to contact one side of said recording medium, and an electrode assembly including a plurality of substantially parallel linear electrodes each having a fine marking edge for contact with the other side of the recording medium and intersecting the first elec trode, each of said linear electrodes being formed of a diiferent metal for reacting with said compound to produce a mark of different color, said linear electrodes being juxtaposed to each other at their marking edges, and a source of alternating current marking signals of variable frequency electrically coupled to the first elec- 5 trode and said electrode assembly.

No references cited. 

